Some chronometers are known which give indications relating to the development of the tide for a specific location, this generally being done by means of needles or a disc moving at a constant speed and essentially giving indications on the situation of the tide in the course of time, without it being possible for exact indications about the level to be obtained. Moreover, some applications comprise mechanisms which take up considerable space and which use a fair amount of energy, unsuitable for use on a chronometer with quartz works.
Moreover, the chronometers known do not enable the development of the tide to be ascertained directly in nominal values of level in consideration of the specific values of the day under consideration, given in the tide directory for principal ports and secondary ports as well as, simultaneously, in consideration of some values concerning a secondary port of specific level situations for a particular predetermined location.